Oil pump



18, E` Hl DAVIS ET AL OIL PUMP Filed July 9, 1930 lin nf l' Patented Apr. 18, 1933 UNITED sTATas PATENT omer. `g

EUGENE H. DAVIS AND WILLIAMS F. JOHNSTON, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNORS OF ONE-FOURTH TO NOAH WALKER, 0F SOMERTON, PENNSYLVANIA, AND ONE-FOURTH 'IO JAMES HARRY THOMPSON; OF TRENTON, NEW JERSEY OIL PUMP Application filed July 9,

Our invention relates to a pump believed to have its widest application in supplying fuel oil to oil burners but intended for other applications to which itis adapted.

A purpose of our invention is to provide equipment of the character indicated adapted to easy and inexpensive manufacture and well suited to the needs of service.

A further purpose is to provide pump equipment of the character indicated adapted to silent operation and free from valves.

A further purpose is to mount a plurality of plungers in the wall of a cylindrical rotor axially transverse to the axes of the plung-v ers, using the rotor movement to reciprocate the plungers in radial bores of the rotor that are angularly spaced around the rotor in a plane perpendicular to the rotor axis.

A further purpose is to increase both the capacity and the uniformity of discharge of a pump including a rotor and plungers therein reciprocatingradially thereof by increasing the number of pump elements.

A further purpose is to provide the outer end of each one of a plurality of radial bores carrying reciprocating plungers with a conduit connection to an inlet conduit as long as the plunger moves along its bore vinwardly and with conduit connection to an outlet connection as long as it moves outwardly.

A further purpose is to reciprocate a plurality of lplungers back and forth along radial bores of arotor cylinderby means of an eccentric connection between the plungers and stationary structure at one end of the cylinder and to provide arcuate inlet and outlet passages between the rotor and its casing intermediate opposite dead centers of the eccentric, sealed from one another at the dead center positions, so that the plungers move radially inward while passing the arcuate inlet, are substantially stationary while passing the dead center seals and move radially outward while passing the arcuate outlet, each rotation of the rotor effecting one complete cycle for each of the plungers, filling its cylinder as the plunger moves radially inward while passing the arcuate inlet and discharging it as it moves radially outward while passing thearcuate outlet connection.

1930. serial No. 456,662.

Further purposes will appear in the specification and in the claims. n i

117e have elected to show one main form only of our invention, showing however fa minor modification andv selecting 'af 4main form land a ymodification thereof that are practical and efficient in operation and which well .illustrate the princ-iples involved.

Figure 1 is a longitudinal section through structure embodying a desirable form 4of an important detail ofour invention.4

Figure 2 is arsection taken upon the line 2-2 of Figure 1.v Y i y 1 ,L

VFigure 3 is a section taken upon the line 3 3 of Figure 1. 1.

.Figure 4 is a reduced scale view correspending to Figure l butshow-ing a somel what different form. f l

Like numerals refer to like parts all figures. v l 1 Describing in illustration and not in limitation and referring to the drawing.

The structure illustrated in Figures 1 to l3 i inclusive includes a cylindrical rotor` 15, stationary supporting and casing structurel and a plurality of radiall plunger-s 17 adapted to reciprocate within radial bores 18k of the rotor during each rotation of the rotor.

The rotor comprises a cylinder 19 rigidly mounted on the end of a shaft 2O driven yin any suitable way, as by a pulley not shown.

The stationary structure includes a body 21 casing the outside circumference andv jone end of the cylinder and a tubular extension 22 around the rotor lshaft providing the shaft with a bearing at 23 and with a packing gland at 24. f p

The stationary structure also includesa cover plate 25 that cases the other end of the cylinder, is rigidly fastened to the body21 and is provided with a slot 26 across the extended axis of the rotor. y t

In the slot 26 we provide a pin bearing 27 which is flanged at 28 inside` the cover, is externally threaded at 29-and bored at 30 95 to receive a pin member 31 that-has a connection with `the plunger-s eccentric with ref spect to the rotor `axis and transversely sliding longitudinally stationary with respect to the individual plungers. 17.

The bearing 27 and therefore the pin 31 is adapted to be set to different positions along the slot 26 in order to vary the maximum eccentricity of the pin with respect to the rotor axis, the pin member 27 being adjusted to the desired position by set screws 32 and 33 that extend into opposite ends of the slot 26 through a boss 34 cn the cover member and clamped in set position by a nut 35.

' The bearing 27 is extended and provided with a suitable wrench hold at 36 for use in holding the member when tightening orploosening the nut 35.

The end of the cylinder is cylindrically hollowed at 37 to provide clearances respectively for the flange 28 at different positions of the b-earing member along the slot 26 and for the eccentric movement with respect to the cylinder of a plunger block 39 which is desirably integral with the pin 31.

The inner ends of the plungers 17 have in'- dividual transverse slide connections with the block 39, being provided with transverse upwardly directed slots 40Y that receive downwardly extending lugs 41 from the bloclr.

The block thusr has no angular movement with respect toany one of the plungers and is shown presenting faces 42 continuously perpendicular to the ends of the respective plungers. Y

rThe lends of the plungers being locked from angular movement with respect to the block rotate the block and pin during the rotation of the cylinder, the eccentricity between the block and cylinder being accommodated by longitudinal movements of the plungers in their respective radial bores and by a relative transverse sliding of the plungers with respect to the block at the lugs 41 along the slots 40. I The slots being continuously transverse to the length of the plungers permits sliding movement between the block and individual plungers at the same time that the plunger impels the plungers to move longitudinally in their respective radial bores.

The rotation of therotor causes reciprocating movements of the plungers in their respective bores,- each plunger alining twice during each rotation with a plane through the parallel axes of the rotor and of the pin.

This plane, indicated by the line 45 of Figure 2 may be called the common dead center position for the individual rplungers, any plunger' being at one end of its range of movement and ltemporarily stationary with respect to the rotor, or'on dead center, each time the plungerjis alined with this line.

We Aprovide a sealing fit between the rotor and its casing at the opposite ends of the dead vcenter line 45, as best seen at 46 and 47 and provide Varcuate passagesv 48 and 49 between the rotor and casing intermediate the sealing fitsat 46 and 47'.

Inlet and outlet ports 50 and 51 connect into passages 48 and 49 which provide conduit connection between the inlet and outlet ports and the ends of the rams respectively during periods of intake during which they are moving radially inward and discharge during which they are moving radially outward with respect to the rotor,

Assuming the direction of rrotation to be that ofthe arrow, any plunger begins to recede, that is to move radially inwardly as soon as it is carried angularly beyond the dead center line, at the seal 46, the movement however being insignificant for a small angular movement beyond the dead Center line, therefore insignificant while the open end of the bore has not yet passed the arcuate sealing surface 46. n

As the open end 43 of any bore is carried. along the passage 48 the radially inwardly moving ram draws liquid from the inlet port 48 while liquid is being expelled from the openy end of the vopposite plunger into the passage 49 and thence into the outlet port 51'.

By the time the open end 43 has been carried to the end of the passage 48 ,the inward stroke of the plunger 'is substantially over, the reverse or outward stroke taking place while the .open end is beingvcarried along the passage 49-a-nd ending at the dead center line. j Y' f i A little before any plunger 'haslrea'ched its dead point the open end of thebore'f-is sealed against the sealing surface of the body. f N

It will be seen that each plunger Acontinuously draws liquid out of ythe passage 48 and of the inlet port 50 while it is open to the passage 48 andthat it continuously expels liquid into the passage 49 and therefore from the outlet port 51 while in connection with the latter passage. j Y

The method of using an eccentric connection between stationary4 supporting structure at an end of the rotor and a plurality of plungers carried by the rotor in order to effect reciprocation of the'plungers along bores radial with respect -to the rotor axis may be widely varied and we illustrate two only of the many different' ways of accomplishing this result, in each case showingan easy adjustment of the strokes of the plungers by an adjustment of the eccentricity of the connection with the stationary' supporting structure.

In the form of Figure 1 in which thepin 31 rotates in an adjustable bearing 27, 'and has transversely slidableV connections with the individual plungers, there is 'an ampleness in the areas of the engaging surfaces of the relatively moving members that makes the formy particularly desirable` from the standpoint of long 2life, without lmaterial wear. o f y In the embodimentshown` in Figure 4 an axially stationary eccentric pin 51 projects inward from a cover plate 52 and presents a roller 53, to the inner ends of the plungers 17.

The eccentricity of the roller 53 with respect to the rotor may be varied to change the throw of the plungers by changing the angular position of the eccentric, as by loosening a clamping sci'ew 54 suitably turning the head r55 and retightening the clamping screw.

The member 51 should be set in the cover plate so that its angular adjustment is accompanied by a minimum shifting of the dead center line 45 away froni a line oining the mid points of the seals 46 and 47.

It should be understood that the line joining the mid points of the sealing surfaces 46 and 47 should be substantially coincident with the line 45 of dead center which is a straight line passing through the axis of the rotor and the axis of the eccentric member.

W'hen the throw of eccentricitv is small a relative small lateral shifting of the center of eccentricity, for example of the center of the roller 53 in Figure 4 effects a relative large angular change in the position-of the dead center line and for this reason with an arcuate adjustment of the eccentricity such as is in Figure 4 where the distance of the axis of the roller 53 from the rotor axis is effected by an angular adjustment of the head 55, there should desirably be a small corrective angular shifting of the cover plate to properly maintain the line of dead centers in its best registry with the sealing surfaces 46 and 47.

Unless the dead center line 45 substantially registers with the mid points of the sealing surfaces 46 and 47 there may be considerable braking upon the rotor when the pistons are passing the seals incident to the movement of the plungers expelling liquid against one sealing surface and leaving a vacuum at the other sealing surface. U

In practice small variations in the position of the dead center line with respect to the line of sealing may not make much difference unless the fitting of the parts is extremely close and we find a groove adjacent one or both of the sealing surfaces, such as indicated at 56, adequately relieves the braking action by permitting the small flow of liquid to get back to the discharge conduit. This return is by leakage between the bearing surfaces.

le prefer the radial slot forni of adjustment of the eccentricity indicated in Figures 1 to 3 to that shown in Figure 4 in that there is no shifting of the line of dead center during the adjustment of the eccentricity and therefore no need for any angular accommodation of the cover plate to correct such shifting, the cover plate 25 being placed upon the body with the slot 26 alining with a line between points of the sealing surfaces 46 pressed inwardly at'57y to present their inner ends in continuous engagement with the roller 53 which forces the plungers radially outwardly while they are passing `along the arcuate'outlet '49 and permits spring retraction of the plungers as they are vpassing the arcuate inlet 48. .i

The accommodation between the pin 53 and the rotor takes place by the longitudinal move-ment ofthe plungers and by transverse sliding of the ends of the plungers with respect to the pin or roller 53. Y A It will be evident that a groovel or release of the character of that shown in 56 may be used to yrelease pressure from the floor of the chamber in tubular extension 22 whenever and however this pressure appears, thus relieving against pressure-of the cylinder 19 against the -cover 25. It will be evident that the number of pistons or plungers may be varied rand themeans of `holding them to movement in andout within the rotor 15 and varying the extent of-this movement may be greatly changed.l y

In view of our invention and disclosure variations and modifications to meet individual whim or particular needwill doubtless becomo evident to others skilled in the art, to obtain all or part of the benefits of our invention without copying the structure shown, and we, therefore, claim all suoli in so far as they fall within the reasonable spirit and scope of our invention.

Having thus described our invention, what we claim as new and desire to secure by. Letters Patent is z- 1. In a device of the character indicated, a shaft axially hollowed at one end and radially bored at circinnferentially spaced intervals into the hollow, a plunger in each bore, a pin having an axis parallel to and laterally offset from the shaft axis, transverse inwardly directed abutments on the plungers continuously engaging and rotating the pin, said abutments pressing the plungers outwardly during their dischargel within the respective bores, said casing in cluding a cover plate across the end of the shaft and having a perforation extending radial of the shaft axis, a support for the iio pin inthe perforation and a screw adjustment between the plate and support adapted to adjust the position of the pin along the perforation in a direction radial of the said shaft axis and substantially along the line connecting the Inid points of said sealing connections.

2. In a device of the character indicated, a shaft axially hollowed at one end and radially bored at circuniferentially spaced `intervals into the hollow, a plunger in each bore, a pin having` an axis parallel to and laterally offset from the shaft axis, transverse inwardly directed abutinents on the lplungers continuously engaging and rotating the pin and thereby pressing the plungers outwardly during their discharge strokes, means for retracting the plungers inwardly during the suction strokes, a stationary casing around the end of the shaft having relatively sealed inlet and outlet connections open into the bores during the inward and outward strokes of the plungers within the respective-bores, said structure being characterized by the stationary casing including a cover plate across the open end of the shaft having a perforation extending in a direction radial of the shaft and substantially alining with the mid points of said sealing connections, a pin bearing in the perforation having an innerv flange engaging the inside of the plate and an eX- ternal nut engaging the outside of the plate, clamping the bearing to the plate between the nut and flange and a screw"V adjustment between the plate and the bearing operating in a direction alining with the said perforation.

EUGENE H. DAVIS. WILLIAM F. JOHNSTON. 

